Nanocomposites with Cellulose Nanocrystals Extracted from Annual Plants

Currently, the massive use of petroleum-based composites is causing many serious environmental problems, which concern the whole society. To reduce their use and gradually replace them with environmentally friendly materials, much research is focused on the development of nanocomposites with bio-based reinforcing elements produced from renewable resources. Among the potential bio-reinforcements, cellulosic fibers contained inside annual plants offer several advantages that allow their use in many sectors such as automotive, construction, food packaging, etc. However, annual plants are currently not being used to their full potential. Some parts of plants are simply not being exploited. The literature abounds with studies on the extraction of cellulose fibers and fibrils as well as nanocrystals that are part of their structure. Cellulose nanocrystals (CNC) often have good reinforcing properties due to their microstructures and high crystallinity. This chapter will first introduce annual plant fibers and their structure. In the second part, the physicochemical properties and extraction processes of nanocrystalline cellulose will be discussed. While the last part will present nanocomposites-based CNC and deal with their morphological, mechanical, thermal barrier and rheological properties.